Newbie CNC mill Control Software

Hello All, Newbie here. I've bought a CNC Ready Mill and am
ready to purchase the control software to interface with it. Is
there a Standard or one that everyone appears to like or has as a
favorite? Cost isn't the primary concern but function-ability is
important, plus reliability. Thanks for your time. I read John's
post and am not interested in his clapped out ford. But an old Jag
would be nice!
Michael :-)